GROFF_DIFF(7) | Miscellaneous Information Manual | GROFF_DIFF(7) |
The section SEE ALSO gives pointers to both the classical roff and the modern groff documentation.
For example, suppose sizescale is 1000; then a scaled point will be equivalent to a millipoint; the call .ps 10.25 is equivalent to .ps 10.25z and so sets the pointsize to 10250 scaled points, which is equal to 10.25 points.
The number register \n[.s] returns the pointsize in points as decimal fraction. There is also a new number register \n[.ps] that returns the pointsize in scaled points.
It would make no sense to use the z scale indicator in a numeric expression whose default scale indicator was neither u nor z, and so troff disallows this. Similarly it would make no sense to use a scaling indicator other than z or u in a numeric expression whose default scale indicator was z, and so troff disallows this as well.
There is also new scale indicator s which multiplies by the number of units in a scaled point. So, for example, \n[.ps]s is equal to 1m. Be sure not to confuse the s and z scale indicators.
M indicates a scale of 100ths of an em. f indicates a scale of 65536 units, providing fractions for color definitions with the defcolor request. For example, 0.5f = 32768u.
The use of \E ensures that these definitions will work even if \*{ gets interpreted in copy-mode (for example, by being used in a macro argument).
\$* \$* \$* \$* \$* \$* \$* \$* \$* \$* \$* \$* \$* \$* \$* \$*
\$* \$* \$* \$* \$* \$* \$* \$*
\$* \$* \$*
would have the same effect as
except that it would work even if compatibility mode had been enabled. Note that the previous compatibility mode is restored before any files sourced by xxx are interpreted.
\$* \$* \$* \$* \$* \$* \$*
\$* \$* \$*
\$* \$* \$* \$* \$* \$* \$* \$* \$*
\$* \$* \$* \$* \$*
will set tabs every half an inch.
The following read/write registers are set by the \w escape sequence:
Other available read/write number registers are:
Fonts not listed in the DESC file are automatically mounted on the next available font position when they are referenced. If a font is to be mounted explicitly with the fp request on an unused font position, it should be mounted on the first unused font position, which can be found in the \n[.fp] register; although troff does not enforce this strictly, it will not allow a font to be mounted at a position whose number is much greater than that of any currently used position.
Interpolating a string does not hide existing macro arguments. Thus in a macro, a more efficient way of doing
is
If the font description file contains pairwise kerning information, glyphs from that font will be kerned. Kerning between two glyphs can be inhibited by placing a \& between them.
In a string comparison in a condition, characters that appear at different input levels to the first delimiter character will not be recognised as the second or third delimiters. This applies also to the tl request. In a \w escape sequence, a character that appears at a different input level to the starting delimiter character will not be recognised as the closing delimiter character. The same is true for \A, \b, \B, \C, \l, \L, \o, \X, and \Z. When decoding a macro or string argument that is delimited by double quotes, a character that appears at a different input level to the starting delimiter character will not be recognised as the closing delimiter character. The implementation of \$@ ensures that the double quotes surrounding an argument will appear the same input level, which will be different to the input level of the argument itself. In a long escape name ] will not be recognized as a closing delimiter except when it occurs at the same input level as the opening ]. In compatibility mode, no attention is paid to the input-level.
There are some new types of condition:
The tr request can now map characters onto \~.
It is now possible to have whitespace between the first and second dot (or the name of the ending macro) to end a macro definition. Example:
\$* \$* \$* \$* \$*
If the tcommand line is present in the DESC file, troff will use the following two commands.
Note that single characters can have the eighth bit set, as can the names of fonts and special characters.
The names of glyphs and fonts can be of arbitrary length; drivers should not assume that they will be only two characters long.
When a glyph is to be printed, that glyph will always be in the current font. Unlike device-independent troff, it is not necessary for drivers to search special fonts to find a glyph.
For color support, some new commands have been added:
The x device control command has been extended.
September 4, 2005 | Groff Version 1.19.2 |